[kentuckytwostep]

tjrider
To understand how the radius arm fails, grab a broom stick with both hands and hold it out infront of you with your elbows at your side bent at a 90 degree angle. now grip the stick real hard and lower one hand (yes, I just said that) and raise the other as if the stick is the axle and your arms are the radius arms. Feel how the broom stick wants to twist in one hand or the other? that is what the axle housing is feeling when radius arms articulate. So you'll either break welds where the axle tubes are pressed into the chunk (what my old XJ did) or it will just bind up and not articulate very well. And what I hated most about radius arms is thier tendency to lift when you accelerate, which is not good when you are climbing a steep ledge/hill.

If you're worried about the single upper do like I did. design your lowers centered with the axle so they take all head on impacts. Then all the upper is doing is preventing the axle from spinning under acceleration or braking. This means that durring forward motion the upper is under compression = no problem :).

Depends on what you want to do. desert race (4link, radius arm) or rock krawl (3link, 4link) or run mud pits (whophucken cares).